This module is basically a class that provides general mechanisms for
parsing strings. It works with my tokenizer
although it can be used with pretty much anything emitting tokens the same
way.
The parser works with a queue of functions. For each token the next function
in the queue is called.

The default behaviour upon receiving a new token is ignoring it. It prints
a warning when reaching EOF with the number of tokens that have been ignored.
However this is probably not what you want to do!

In order to parse what you need to parse you have to provide the parser
with the functions which will be called for each token. Let's call these
functions 'handlers'.
This can be achieved through configuration of the basic parser or
through inheritance.

var Parser =require('parser');

var util =require('util');

var MyTokenizer =require('./MyTokenizer');

functionMyParser(){

// MyTokenizer is the tokenizer we configured

// but it's not the subject of this module

Parser.apply(this,newMyTokenizer());

// override the default behaviour

this.defaultHandler(this.default);

// specify the function that will be called on the first token

this.initialHander(this.initial);

}

util.inherits(MyParser, Parser);

/**

* Of course you will have to define these functions somewhere

*/

This is very theoretic but you can have a look at what is in the example
folder

Handlers are just javascript functions accepting the following arguments:

token the actual token emitted by the tokenizer

type the type of this token (i.e. 'number', 'whitespace', 'word')

next a function to specify what needs to be called on the next token(s)

the next function takes a random number of handlers which will be pushed
in front of the handlers queue (they will be next!).
returning true from a handler causes the same token to be reemitted
to the next handler.

This allows you to define handlers doing some kind of "sniffing" if you find
yourself in a state in which you cannot determine what will come next.
This kind of handlers expand themselves to a greater number of handlers that
will effectively parse the following tokens. They do that by adding a few handlers
to the queue with next and returning true to notify the parser that the token
should be reemitted.

checkType(type) returns a handler that only checks the type of the
token without doing anything so the same token is pass down to the next
handler

expect(type) returns a handler that checks for the specified type
and consumes the token

list(separator, element, end) returns a handler expanding to the
handlers needed to parse a list of elements able to be parsed by element
and separated by tokens of type separator. The list should end by a
token of type end